Study On Different Residue Hydrotreating And Coking Characteristics

At present,although the international crude oil prices are low,the crude oil reserves has declined year by year,the poor heavy oil production increased year by year.It is very important to improve the utilization of heavy crude oil,especially improve the utilization of residual oil.Catalytic hydrogenation technology can not only improve the utilization of heavy crude oil and residue,but also can effectively improve the quality of the product.Therefore,it is necessary to study the heavy oil properties effect on the catalytic hydrogenation and the tendency of coke.Catalytic hydrogenation is the main method to improve the utilization rate of crude oil,and the catalytic hydrogenation of residual oil is of concern.In this paper,five different sources of residue were used as raw materials,the catalytic hydrotreating was carried out in high pressure autoclave,to study the hydrogenation reaction performance by changing the reaction conditions.In addition,the relationship between the structural parameters of heavy oil and the performance of hydrogenation,the correlation between the properties of heavy oil and the coke tendency in the radial section of the catalyst were investigated.Under the same reaction conditions,the trendences of coke yield are same,but for the gas,gasoline,diesel and other products,the yield changes and the properties of heavy oil changes are closely related,especially the light oil yield and the heavy oil conversion are closely related to the relative content of asphaltenes,the higher the asphaltene content is,the lower the light oil yield and the heavy oil conversion,which are also related to other factors.For heavy oil,the H/C and fa,Ca,CI and other structural parameters and heavy oil hydrogenation product distribution is closely related,to the light oil yield and heavy oil conversion rate go up with growth of fa,Ca and CI value as a whole.In addition,the coke yield decreases with decrease of the characteristic parameter increases as a whole.The characterization parameter is an important parameter to measure the effect of catalytic hydrogenation.During the hydrogenation of residual oil,asphaltene is the main source of coke,and its content and coke production rate also show a certain law,in addition to the coke yield and heavy oil relative molecular weight,viscosity and aroma and other factors.Coke deposition in the the pores and the surface of catalyst will affect the catalytic hydrogenation reaction effect.When the geometrical center of the radial section of the catalyst is farther away,the deposition amount of the coke is larger and the growth rate of the coke is increasing,and the growth rate of the coke and the deposition amount are maximized on the surface.In addition,the amount of coke in the catalyst is determined by the average relative molecular weight,viscosity,aroma and other factors of heavy oil.The relative content of aromatic carbon in coke is generally higher than that of aliphatic carbon,and the higher the aromaticity,the higher the relative content of aromatic carbon in coke.